/*
Stockfish, a UCI chess playing engine derived from Glaurung 2.1
Copyright (C) 2004-2008 Tord Romstad (Glaurung author)
- Copyright (C) 2008-2010 Marco Costalba, Joona Kiiski, Tord Romstad
+ Copyright (C) 2008-2012 Marco Costalba, Joona Kiiski, Tord Romstad
Stockfish is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
+#include <algorithm>
#include <cassert>
#include <cstring>
-#include <map>
#include "material.h"
{ 41, 41, 41, 41, 41, 41 }, { 37, 41, 41, 41, 41, 41 }, { 10, 62, 41, 41, 41, 41 },
{ 57, 64, 39, 41, 41, 41 }, { 50, 40, 23, -22, 41, 41 }, { 106, 101, 3, 151, 171, 41 } };
- typedef EndgameEvaluationFunctionBase EF;
- typedef EndgameScalingFunctionBase SF;
- typedef map<Key, EF*> EFMap;
- typedef map<Key, SF*> SFMap;
-
// Endgame evaluation and scaling functions accessed direcly and not through
// the function maps because correspond to more then one material hash key.
- EvaluationFunction<KmmKm> EvaluateKmmKm[] = { EvaluationFunction<KmmKm>(WHITE), EvaluationFunction<KmmKm>(BLACK) };
- EvaluationFunction<KXK> EvaluateKXK[] = { EvaluationFunction<KXK>(WHITE), EvaluationFunction<KXK>(BLACK) };
- ScalingFunction<KBPsK> ScaleKBPsK[] = { ScalingFunction<KBPsK>(WHITE), ScalingFunction<KBPsK>(BLACK) };
- ScalingFunction<KQKRPs> ScaleKQKRPs[] = { ScalingFunction<KQKRPs>(WHITE), ScalingFunction<KQKRPs>(BLACK) };
- ScalingFunction<KPsK> ScaleKPsK[] = { ScalingFunction<KPsK>(WHITE), ScalingFunction<KPsK>(BLACK) };
- ScalingFunction<KPKP> ScaleKPKP[] = { ScalingFunction<KPKP>(WHITE), ScalingFunction<KPKP>(BLACK) };
+ Endgame<KmmKm> EvaluateKmmKm[] = { Endgame<KmmKm>(WHITE), Endgame<KmmKm>(BLACK) };
+ Endgame<KXK> EvaluateKXK[] = { Endgame<KXK>(WHITE), Endgame<KXK>(BLACK) };
+
+ Endgame<KBPsK> ScaleKBPsK[] = { Endgame<KBPsK>(WHITE), Endgame<KBPsK>(BLACK) };
+ Endgame<KQKRPs> ScaleKQKRPs[] = { Endgame<KQKRPs>(WHITE), Endgame<KQKRPs>(BLACK) };
+ Endgame<KPsK> ScaleKPsK[] = { Endgame<KPsK>(WHITE), Endgame<KPsK>(BLACK) };
+ Endgame<KPKP> ScaleKPKP[] = { Endgame<KPKP>(WHITE), Endgame<KPKP>(BLACK) };
// Helper templates used to detect a given material distribution
template<Color Us> bool is_KXK(const Position& pos) {
&& pos.piece_count(Them, ROOK) == 1
&& pos.piece_count(Them, PAWN) >= 1;
}
-}
-
-
-/// EndgameFunctions class stores endgame evaluation and scaling functions
-/// in two std::map. Because STL library is not guaranteed to be thread
-/// safe even for read access, the maps, although with identical content,
-/// are replicated for each thread. This is faster then using locks.
-
-class EndgameFunctions {
-public:
- EndgameFunctions();
- ~EndgameFunctions();
- template<class T> T* get(Key key) const;
-
-private:
- template<class T> void add(const string& keyCode);
-
- static Key buildKey(const string& keyCode);
- static const string swapColors(const string& keyCode);
-
- // Here we store two maps, for evaluate and scaling functions...
- pair<EFMap, SFMap> maps;
-
- // ...and here is the accessing template function
- template<typename T> const map<Key, T*>& get() const;
-};
-
-// Explicit specializations of a member function shall be declared in
-// the namespace of which the class template is a member.
-template<> const EFMap& EndgameFunctions::get<EF>() const { return maps.first; }
-template<> const SFMap& EndgameFunctions::get<SF>() const { return maps.second; }
+} // namespace
-/// MaterialInfoTable c'tor and d'tor allocate and free the space for EndgameFunctions
-MaterialInfoTable::MaterialInfoTable() { funcs = new EndgameFunctions(); }
-MaterialInfoTable::~MaterialInfoTable() { delete funcs; }
+/// MaterialTable::probe() takes a position object as input, looks up a MaterialEntry
+/// object, and returns a pointer to it. If the material configuration is not
+/// already present in the table, it is computed and stored there, so we don't
+/// have to recompute everything when the same material configuration occurs again.
+MaterialEntry* MaterialTable::probe(const Position& pos) {
-/// MaterialInfoTable::get_material_info() takes a position object as input,
-/// computes or looks up a MaterialInfo object, and returns a pointer to it.
-/// If the material configuration is not already present in the table, it
-/// is stored there, so we don't have to recompute everything when the
-/// same material configuration occurs again.
+ Key key = pos.material_key();
+ MaterialEntry* e = entries[key];
-MaterialInfo* MaterialInfoTable::get_material_info(const Position& pos) const {
-
- Key key = pos.get_material_key();
- MaterialInfo* mi = find(key);
-
- // If mi->key matches the position's material hash key, it means that we
+ // If e->key matches the position's material hash key, it means that we
// have analysed this material configuration before, and we can simply
// return the information we found the last time instead of recomputing it.
- if (mi->key == key)
- return mi;
-
- // Initialize MaterialInfo entry
- memset(mi, 0, sizeof(MaterialInfo));
- mi->key = key;
- mi->factor[WHITE] = mi->factor[BLACK] = (uint8_t)SCALE_FACTOR_NORMAL;
+ if (e->key == key)
+ return e;
- // Store game phase
- mi->gamePhase = MaterialInfoTable::game_phase(pos);
+ memset(e, 0, sizeof(MaterialEntry));
+ e->key = key;
+ e->factor[WHITE] = e->factor[BLACK] = (uint8_t)SCALE_FACTOR_NORMAL;
+ e->gamePhase = MaterialTable::game_phase(pos);
// Let's look if we have a specialized evaluation function for this
// particular material configuration. First we look for a fixed
// configuration one, then a generic one if previous search failed.
- if ((mi->evaluationFunction = funcs->get<EF>(key)) != NULL)
- return mi;
+ if (endgames.probe(key, e->evaluationFunction))
+ return e;
if (is_KXK<WHITE>(pos))
{
- mi->evaluationFunction = &EvaluateKXK[WHITE];
- return mi;
+ e->evaluationFunction = &EvaluateKXK[WHITE];
+ return e;
}
if (is_KXK<BLACK>(pos))
{
- mi->evaluationFunction = &EvaluateKXK[BLACK];
- return mi;
+ e->evaluationFunction = &EvaluateKXK[BLACK];
+ return e;
}
if (!pos.pieces(PAWN) && !pos.pieces(ROOK) && !pos.pieces(QUEEN))
{
// Minor piece endgame with at least one minor piece per side and
// no pawns. Note that the case KmmK is already handled by KXK.
- assert((pos.pieces(KNIGHT, WHITE) | pos.pieces(BISHOP, WHITE)));
- assert((pos.pieces(KNIGHT, BLACK) | pos.pieces(BISHOP, BLACK)));
+ assert((pos.pieces(WHITE, KNIGHT) | pos.pieces(WHITE, BISHOP)));
+ assert((pos.pieces(BLACK, KNIGHT) | pos.pieces(BLACK, BISHOP)));
if ( pos.piece_count(WHITE, BISHOP) + pos.piece_count(WHITE, KNIGHT) <= 2
&& pos.piece_count(BLACK, BISHOP) + pos.piece_count(BLACK, KNIGHT) <= 2)
{
- mi->evaluationFunction = &EvaluateKmmKm[WHITE];
- return mi;
+ e->evaluationFunction = &EvaluateKmmKm[pos.side_to_move()];
+ return e;
}
}
//
// We face problems when there are several conflicting applicable
// scaling functions and we need to decide which one to use.
- SF* sf;
+ EndgameBase<ScaleFactor>* sf;
- if ((sf = funcs->get<SF>(key)) != NULL)
+ if (endgames.probe(key, sf))
{
- mi->scalingFunction[sf->color()] = sf;
- return mi;
+ e->scalingFunction[sf->color()] = sf;
+ return e;
}
// Generic scaling functions that refer to more then one material
// distribution. Should be probed after the specialized ones.
// Note that these ones don't return after setting the function.
if (is_KBPsKs<WHITE>(pos))
- mi->scalingFunction[WHITE] = &ScaleKBPsK[WHITE];
+ e->scalingFunction[WHITE] = &ScaleKBPsK[WHITE];
if (is_KBPsKs<BLACK>(pos))
- mi->scalingFunction[BLACK] = &ScaleKBPsK[BLACK];
+ e->scalingFunction[BLACK] = &ScaleKBPsK[BLACK];
if (is_KQKRPs<WHITE>(pos))
- mi->scalingFunction[WHITE] = &ScaleKQKRPs[WHITE];
+ e->scalingFunction[WHITE] = &ScaleKQKRPs[WHITE];
else if (is_KQKRPs<BLACK>(pos))
- mi->scalingFunction[BLACK] = &ScaleKQKRPs[BLACK];
+ e->scalingFunction[BLACK] = &ScaleKQKRPs[BLACK];
Value npm_w = pos.non_pawn_material(WHITE);
Value npm_b = pos.non_pawn_material(BLACK);
if (pos.piece_count(BLACK, PAWN) == 0)
{
assert(pos.piece_count(WHITE, PAWN) >= 2);
- mi->scalingFunction[WHITE] = &ScaleKPsK[WHITE];
+ e->scalingFunction[WHITE] = &ScaleKPsK[WHITE];
}
else if (pos.piece_count(WHITE, PAWN) == 0)
{
assert(pos.piece_count(BLACK, PAWN) >= 2);
- mi->scalingFunction[BLACK] = &ScaleKPsK[BLACK];
+ e->scalingFunction[BLACK] = &ScaleKPsK[BLACK];
}
else if (pos.piece_count(WHITE, PAWN) == 1 && pos.piece_count(BLACK, PAWN) == 1)
{
// This is a special case because we set scaling functions
// for both colors instead of only one.
- mi->scalingFunction[WHITE] = &ScaleKPKP[WHITE];
- mi->scalingFunction[BLACK] = &ScaleKPKP[BLACK];
+ e->scalingFunction[WHITE] = &ScaleKPKP[WHITE];
+ e->scalingFunction[BLACK] = &ScaleKPKP[BLACK];
}
}
// No pawns makes it difficult to win, even with a material advantage
if (pos.piece_count(WHITE, PAWN) == 0 && npm_w - npm_b <= BishopValueMidgame)
{
- mi->factor[WHITE] =
- (npm_w == npm_b || npm_w < RookValueMidgame ? 0 : NoPawnsSF[Min(pos.piece_count(WHITE, BISHOP), 2)]);
+ e->factor[WHITE] = (uint8_t)
+ (npm_w == npm_b || npm_w < RookValueMidgame ? 0 : NoPawnsSF[std::min(pos.piece_count(WHITE, BISHOP), 2)]);
}
if (pos.piece_count(BLACK, PAWN) == 0 && npm_b - npm_w <= BishopValueMidgame)
{
- mi->factor[BLACK] =
- (npm_w == npm_b || npm_b < RookValueMidgame ? 0 : NoPawnsSF[Min(pos.piece_count(BLACK, BISHOP), 2)]);
+ e->factor[BLACK] = (uint8_t)
+ (npm_w == npm_b || npm_b < RookValueMidgame ? 0 : NoPawnsSF[std::min(pos.piece_count(BLACK, BISHOP), 2)]);
}
// Compute the space weight
int minorPieceCount = pos.piece_count(WHITE, KNIGHT) + pos.piece_count(WHITE, BISHOP)
+ pos.piece_count(BLACK, KNIGHT) + pos.piece_count(BLACK, BISHOP);
- mi->spaceWeight = minorPieceCount * minorPieceCount;
+ e->spaceWeight = minorPieceCount * minorPieceCount;
}
// Evaluate the material imbalance. We use PIECE_TYPE_NONE as a place holder
{ pos.piece_count(BLACK, BISHOP) > 1, pos.piece_count(BLACK, PAWN), pos.piece_count(BLACK, KNIGHT),
pos.piece_count(BLACK, BISHOP) , pos.piece_count(BLACK, ROOK), pos.piece_count(BLACK, QUEEN) } };
- mi->value = (int16_t)(imbalance<WHITE>(pieceCount) - imbalance<BLACK>(pieceCount)) / 16;
- return mi;
+ e->value = (int16_t)((imbalance<WHITE>(pieceCount) - imbalance<BLACK>(pieceCount)) / 16);
+ return e;
}
-/// MaterialInfoTable::imbalance() calculates imbalance comparing piece count of each
+/// MaterialTable::imbalance() calculates imbalance comparing piece count of each
/// piece type for both colors.
template<Color Us>
-int MaterialInfoTable::imbalance(const int pieceCount[][8]) {
+int MaterialTable::imbalance(const int pieceCount[][8]) {
const Color Them = (Us == WHITE ? BLACK : WHITE);
- int pt1, pt2, pc, vv;
+ int pt1, pt2, pc, v;
int value = 0;
// Redundancy of major pieces, formula based on Kaufman's paper
+ RedundantQueenPenalty * pieceCount[Us][QUEEN];
// Second-degree polynomial material imbalance by Tord Romstad
- for (pt1 = PIECE_TYPE_NONE; pt1 <= QUEEN; pt1++)
+ for (pt1 = NO_PIECE_TYPE; pt1 <= QUEEN; pt1++)
{
pc = pieceCount[Us][pt1];
if (!pc)
continue;
- vv = LinearCoefficients[pt1];
+ v = LinearCoefficients[pt1];
- for (pt2 = PIECE_TYPE_NONE; pt2 <= pt1; pt2++)
- vv += QuadraticCoefficientsSameColor[pt1][pt2] * pieceCount[Us][pt2]
- + QuadraticCoefficientsOppositeColor[pt1][pt2] * pieceCount[Them][pt2];
+ for (pt2 = NO_PIECE_TYPE; pt2 <= pt1; pt2++)
+ v += QuadraticCoefficientsSameColor[pt1][pt2] * pieceCount[Us][pt2]
+ + QuadraticCoefficientsOppositeColor[pt1][pt2] * pieceCount[Them][pt2];
- value += pc * vv;
+ value += pc * v;
}
return value;
}
-/// MaterialInfoTable::game_phase() calculates the phase given the current
+/// MaterialTable::game_phase() calculates the phase given the current
/// position. Because the phase is strictly a function of the material, it
-/// is stored in MaterialInfo.
+/// is stored in MaterialEntry.
-Phase MaterialInfoTable::game_phase(const Position& pos) {
+Phase MaterialTable::game_phase(const Position& pos) {
Value npm = pos.non_pawn_material(WHITE) + pos.non_pawn_material(BLACK);
- if (npm >= MidgameLimit)
- return PHASE_MIDGAME;
-
- if (npm <= EndgameLimit)
- return PHASE_ENDGAME;
-
- return Phase(((npm - EndgameLimit) * 128) / (MidgameLimit - EndgameLimit));
-}
-
-
-/// EndgameFunctions member definitions
-
-EndgameFunctions::EndgameFunctions() {
-
- add<EvaluationFunction<KNNK> >("KNNK");
- add<EvaluationFunction<KPK> >("KPK");
- add<EvaluationFunction<KBNK> >("KBNK");
- add<EvaluationFunction<KRKP> >("KRKP");
- add<EvaluationFunction<KRKB> >("KRKB");
- add<EvaluationFunction<KRKN> >("KRKN");
- add<EvaluationFunction<KQKR> >("KQKR");
- add<EvaluationFunction<KBBKN> >("KBBKN");
-
- add<ScalingFunction<KNPK> >("KNPK");
- add<ScalingFunction<KRPKR> >("KRPKR");
- add<ScalingFunction<KBPKB> >("KBPKB");
- add<ScalingFunction<KBPPKB> >("KBPPKB");
- add<ScalingFunction<KBPKN> >("KBPKN");
- add<ScalingFunction<KRPPKRP> >("KRPPKRP");
-}
-
-EndgameFunctions::~EndgameFunctions() {
-
- for (EFMap::const_iterator it = maps.first.begin(); it != maps.first.end(); ++it)
- delete it->second;
-
- for (SFMap::const_iterator it = maps.second.begin(); it != maps.second.end(); ++it)
- delete it->second;
-}
-
-Key EndgameFunctions::buildKey(const string& keyCode) {
-
- assert(keyCode.length() > 0 && keyCode.length() < 8);
- assert(keyCode[0] == 'K');
-
- string fen;
- bool upcase = false;
-
- // Build up a fen string with the given pieces, note that
- // the fen string could be of an illegal position.
- for (size_t i = 0; i < keyCode.length(); i++)
- {
- if (keyCode[i] == 'K')
- upcase = !upcase;
-
- fen += char(upcase ? toupper(keyCode[i]) : tolower(keyCode[i]));
- }
- fen += char(8 - keyCode.length() + '0');
- fen += "/8/8/8/8/8/8/8 w - -";
- return Position(fen, false, 0).get_material_key();
-}
-
-const string EndgameFunctions::swapColors(const string& keyCode) {
-
- // Build corresponding key for the opposite color: "KBPKN" -> "KNKBP"
- size_t idx = keyCode.find('K', 1);
- return keyCode.substr(idx) + keyCode.substr(0, idx);
-}
-
-template<class T>
-void EndgameFunctions::add(const string& keyCode) {
-
- typedef typename T::Base F;
- typedef map<Key, F*> M;
-
- const_cast<M&>(get<F>()).insert(pair<Key, F*>(buildKey(keyCode), new T(WHITE)));
- const_cast<M&>(get<F>()).insert(pair<Key, F*>(buildKey(swapColors(keyCode)), new T(BLACK)));
-}
-
-template<class T>
-T* EndgameFunctions::get(Key key) const {
-
- typename map<Key, T*>::const_iterator it = get<T>().find(key);
- return it != get<T>().end() ? it->second : NULL;
+ return npm >= MidgameLimit ? PHASE_MIDGAME
+ : npm <= EndgameLimit ? PHASE_ENDGAME
+ : Phase(((npm - EndgameLimit) * 128) / (MidgameLimit - EndgameLimit));
}